Building self confidence is the key to spiritual, mental, and physical health.  The way to build self confidence is doing things your not sure you can do.  Doing things your sure you can do, like drinking a beer, won't improve matters.  So the way to build self confidence is doing things you're not sure you can do.  Whatever it is, the trick is to stop thinking about it and do it.  Seize the day and things will become easier and easier.  To keep your self confidence, keep giving yourself new challenges, making sure they are new ones and not the same old tricks in new disguises.  

thoughts from the book "Das Energi"  by Paul Williams  (an amazing book)